Anachronism in the reform of liturgy is no virtue.
Organic development is no vice.
Johnny Hixson quotes Pius XII on Facebook:
"Thus, to cite some instances, one would be straying from the straight path were he to wish the altar restored to its primitive table form; were he to want black excluded as a color for the liturgical vestments; were he to forbid the use of sacred images and statues in Churches; were he to order the crucifix so designed that the divine Redeemer's body shows no trace of His cruel sufferings; and lastly were he to disdain and reject polyphonic music or singing in parts, even where it conforms to regulations issued by the Holy See."
-Pope Pius XII, Mediator Dei, November 20, 1947
A few observations:
I have not checked the accuracy of the translation, but"straying from the straight path" sounds too much like a Maoism. Pius forgive me (or is it your translator?)
In paragraph 64, Pius XII rejects "senseless antiquarianism." I agree. Mr. Hixson's quote is from Paragraph 62 and should be read in this context. Benedict has explained this with great theological insight both now and before his papacy. Renewing the liturgy is central to renewing the church. Wrecking the liturgy to reconstruct some scholar's mistaken imagining of how the primitive church must have performed the liturgy is not renewal.
In the context of all three paragraphs of Mediator Dei, Pius rejects those who attack as inauthentic any development of the liturgy after that of the primitive church, i.e., as reconstructed in the mind models of scholars. He himself reformed the Holy Week liturgy which is how it came to its form in the Missal of John XXIII: the 1962 Missal commonly used as the missal in the Extraordinary Form of the Roman Rite.
Personally I believe that the idea the altar should be a Renaissance dinner table is anachronistic. Whether the table is like Michelangelo's Last Supper or Luther's Tisch, it is neither like what Christ sat at nor like the altar in the Jewish Temple. Both are Renaissance projections back to the first century: "senseless antiquarianism."
Personally I love sacred polyphony, but prefer chant in mass and think every mass should be chanted. I would eliminate low masses other than private masses and under extraordinary circumstances. Music after Praetorius, even that of divine Mozart, robs the congregation of its rightful role. This is a tragedy of the reductionist reforms of Trent. It is even true even of my beloved Renaissance polyphony. Am I throwing the baby out with the bath water? Tallis forgive me!